What labs and imaging should be ordered for a patient with a history of significant head injury presenting with acute onset of aphasia, choking, and lower back tightness?

Imaging for Post-Head Injury Patient with Acute Neurological Symptoms

For a patient with history of significant head injury presenting with acute onset aphasia, choking during sleep, and lower back tightness, noncontrast head CT is the most appropriate initial imaging study, followed by brain MRI if CT findings are negative or do not explain the neurological symptoms. 1

Initial Imaging Approach

Primary Imaging

1. Noncontrast Head CT

   • First-line imaging test for acute neurological changes in a patient with prior TBI 1
   • Rapidly identifies potentially life-threatening conditions requiring immediate intervention:
     • Intracranial hemorrhage
     • Mass effect
     • Hydrocephalus
     • Midline shift
     • Evidence of increased intracranial pressure

2. Cervical Spine Imaging

   • Given the patient's lower back tightness and inability to walk:
     • Noncontrast CT of cervical spine to evaluate for acute injury 1
     • Consider extending to thoracic/lumbar spine based on neurological exam findings

Secondary Imaging (if initial CT is negative or inconclusive)

1. Brain MRI without contrast

   • Superior for detecting subtle abnormalities not visible on CT 1
   • Particularly valuable in this case with:
     • Unexplained neurological deficits (aphasia)
     • Prior significant head trauma
     • Symptoms not explained by initial CT findings 1

2. Specific MRI sequences to include:

   • T2*-weighted and susceptibility-weighted imaging (SWI) sequences
     • Highly sensitive for detecting microhemorrhages and axonal injury 1
     • Can detect 30% more TBI-related lesions compared to CT 1
   • Diffusion-weighted imaging (DWI)
     • Essential for detecting acute ischemic changes

Laboratory Testing

Essential Labs

1. Complete blood count

   • To evaluate for infection or anemia that could contribute to neurological symptoms

2. Basic metabolic panel

   • To assess for metabolic causes of altered mental status
   • Particularly important given history of choking episode

3. Coagulation studies (PT/INR)

   • Important in a patient with history of TBI and potential risk of hemorrhage 2

Clinical Decision Algorithm

1. If noncontrast head CT shows acute findings:

   • Manage according to findings (neurosurgical consultation for hemorrhage, mass effect)
   • Consider CTA of head and neck if vascular injury is suspected 1

2. If noncontrast head CT is negative but symptoms persist:

   • Proceed to brain MRI without contrast 1
   • Include T2*, SWI, and DWI sequences 1

3. If both CT and conventional MRI are negative:

   • Consider advanced neuroimaging techniques:
     • MRI diffusion tensor imaging
     • Functional MRI
     • MR spectroscopy 1

Important Considerations

Potential Pitfalls to Avoid

1. Relying solely on CT imaging

   • CT has limited sensitivity (approximately 10%) for early posterior fossa ischemic changes 2
   • May miss subtle traumatic axonal injury that could explain symptoms 1

2. Dismissing symptoms due to prior head injury

   • Acute changes in neurological status require thorough evaluation
   • The choking episode suggests potential brainstem or cranial nerve involvement

3. Neglecting spinal evaluation

   • Lower back tightness and inability to walk warrant spinal imaging
   • Consider both structural and neurological causes

Special Considerations for This Patient

• The combination of aphasia and choking raises concern for brainstem involvement or possible cerebrospinal fluid leak 1
• History of significant head injury increases risk of delayed complications including post-traumatic seizures, which could explain the episode
• Age (41 years) and mechanism of prior injury (20-foot fall) increase risk of significant intracranial pathology 1

The American College of Radiology guidelines strongly support this imaging approach for patients with neurological deterioration following traumatic brain injury, emphasizing that brain MRI is particularly valuable when CT findings do not explain persistent neurological deficits 1.